The medical environment tends to generate three main forms of trash: sharps, biohazard materials, and ordinary trash. Hospital staff tends to waste money by negligently discarding equipment after surgery, typically by unintentionally depositing metal items (e.g., surgical tools) into the trash along with disposable garments (surgical “scrubs”) and other potentially hazardous biological waste. The incorporation of a metal detector with a trash can helps to alleviate this problem.
Medical environments outside the hospital (e.g., doctors' offices, hospital rooms, and surgical suites) must also put proper protocols into place for the safe disposal of “sharps”. Federal regulations (e.g., 49 CFR 173.134) define a “sharp” as any object that may be contaminated with a pathogen and that is capable of cutting or penetrating skin or a packaging material (and thus leading to injury or disease transmission or both). Sharps include items such as needles, scalpels, broken glass, culture dishes, etc. Federal regulations (e.g., 49 CFR 173.197) require that sharps be placed in containers that are rigid, leak resistant, impervious to moisture, strong enough to prevent tearing or bursting during normal conditions of transport, and puncture resistant.
U.S. hospitals produce an estimated 6,600 tons of waste daily and 4,000,000,000 pounds annually. Within the hospital, operating rooms tend to generate two main forms of trash: single use sterilized equipment and regular garbage which is sometimes needlessly bagged as hazardous waste. The well-recognized red bags are intended to be used for medical waste that requires more cautious—and thus more expensive—disposal procedures. Some research indicates, however, that up to 90% of items disposed in special red bags are simply regular trash that could be stored in a clear bag and disposed of more conveniently. Thus, a more efficient segregation and disposal of trash could provide significant cost savings in the healthcare industry.
Medical disposal and detector systems currently available have a number of shortcomings. In some, the openings are unfinished and expose the contents of a biohazard bag. The structural materials ear and lack the rigidity of conventional industrial disposals. Because a sterile environment is a fundamental hospital goal, certain types of plastics—especially inexpensive ones—do not necessarily reassure the user as to their cleanliness. Some plastics interact slightly with hospital cleaning materials and develop an undesired sticky texture. In some cases the structures are angular with protruding surfaces and corners, which in turn can catch on medical clothing and draping.
Many structures are singular in their function, so that separate items are needed for the several types of expected waste, which in turn tends to crowd the medical space in an undesired, or in some cases an unsafe or unsanitary, manner.
Appropriate devices must also meet medical regulations for safely storing biohazard materials. The Bloodborne Pathogens Standard of the U.S. Occupational Safety and Health Administration (OSHA) uses the term “regulated waste” to refer to waste items such as:                liquid or semi-liquid blood or other potentially infectious materials (OPIM);        items contaminated with blood or OPIM and which would release these substances in a liquid or semi-liquid state if compressed;        items that are caked with dried blood or OPIM and are capable of releasing these materials during handling;        contaminated sharps; and        pathological and microbiological wastes containing blood or OPIM.With these standards in place, disposal devices generally accept the standard “red bag” used in the hospital environment. The device must be waterproof so that it can be cleaned easily and completely and those portions of devices that are in contact with hazardous materials must be formed of a material that is impermeable rather than porous.        
Changing a bag in conventional devices can be both time consuming and inefficient due to their structure and configuration. Systems that require significant user strength are unacceptable in the hospital environment because much work is done by smaller persons. For example, on a percentile basis, in order to capture 99% of potential users, the device should be easily handled by a middle-age female. Additionally, existing devices may preclude access to the full bag or to new bags, are sometimes improperly balanced, may not withstand the weight strain of an overly full or leaning load, and do not offer any method of separating large and small biohazard materials, or provide a separate area for disposing of non biohazard materials.
Additionally, loss of expensive metallic items such as tools, templates, and other devices plague industries which are unrelated to medicine such as machine shops, automobile garages, assembly plants, laboratories, manufacturing plants, and similar facilities. These industries will benefit equally from a newly improved waste cart.
Hence, a need exists for a waste cart capable of detecting metallic objects as they pass through the cart's openings.